首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   37110篇
  免费   1414篇
  国内免费   11篇
  2018年   564篇
  2017年   607篇
  2016年   628篇
  2015年   466篇
  2014年   605篇
  2013年   3200篇
  2012年   1027篇
  2011年   1110篇
  2010年   732篇
  2009年   713篇
  2008年   1086篇
  2007年   994篇
  2006年   963篇
  2005年   893篇
  2004年   876篇
  2003年   871篇
  2002年   908篇
  2001年   852篇
  2000年   824篇
  1999年   711篇
  1998年   467篇
  1997年   472篇
  1996年   433篇
  1995年   427篇
  1992年   650篇
  1991年   593篇
  1990年   587篇
  1989年   541篇
  1988年   551篇
  1987年   524篇
  1986年   555篇
  1985年   570篇
  1984年   557篇
  1983年   515篇
  1982年   432篇
  1981年   434篇
  1979年   534篇
  1978年   494篇
  1977年   429篇
  1976年   448篇
  1975年   471篇
  1974年   577篇
  1973年   558篇
  1972年   412篇
  1971年   424篇
  1970年   397篇
  1969年   421篇
  1968年   500篇
  1967年   452篇
  1966年   465篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
981.
Subjects (average age 21 years, recruited by personal contact and through a school) were presented with a spoken sentence on tape and then heard six speakers of the same sex, including the original speaker, say the same sentence. They were required to indicate which was the original speaker. The task was repeated with seven different sentences and sets of speakers. One group of subjects heard short sentences containing an average of 2.14 different vowel sounds and 6.28 syllables, another group heard short sentences containing an average of 6.14 vowel sounds (7.28 syllables) and a third group heard longer sentences containing an average of 6.28 vowel sounds (11.00 syllables). Accuracy of speaker identification improved significantly when more vowel sounds were heard, but increased sentence length had no significant effect on performance. Performance was significantly better when the listener was the same sex as the speaker than when the listener was of the other sex.  相似文献   
982.
This investigation focused on the interrelationships among students' study activities, students' self-concept of academic ability ratings, students' academic achievement, and instructional practices in 12 high school biology courses. Using a framework derived from a previous investigation, course features were classified into those that appear to (a) place demands on, (b) support, or (c) compensate for student engagement in particular study activities. Students' study activities, self-concept of academic ability ratings, and achievement were measured with experimenter-developed instruments. Results are reported for (a) characteristics of instruments and course features, (b) relationships between central factors of the investigation, and (c) multi-level relationships between course features and student variables. Results at the student level indicated that self-concept of academic ability and, to a lesser extent, students' study activities were positively associated with student achievement. Students' self-concept of academic ability ratings were also linked to students' engagement in generative, proactive study activities. At the course level the supportive practices of providing challenging homework assignments and extensive feedback on student coursework were associated with student engagement in effortful, generative, proactive study activities. The provision of extensive feedback was also associated with high student achievement. Multi-level relationships were analysed using hierarchical linear modelling (HLM) analyses. These analyses revealed, for example, that in courses in which little or no feedback is given on homework assignments, the relationship between achievement and student engagement in diligent effort management activities was enhanced. Other HLM analyses were conducted to examine the mediating role of course features on the relationship between students' self-concept of academic ability and their study activities and achievement. For example, the presence of challenging course demands was associated with an enhancement of the relationship between self-concept of academic ability and achievement whereas the presence of instructor provisions (supports and compensations) designed to reduce course demands was associated with a reduction in this relationship.  相似文献   
983.
Personnel Reaction Blank (PRB) scores and biographical data were obtained from two groups of registered nurses; a deviant group, represented by those who had official actions taken against their nursing license by the Minnesota Board of Nursing (n=53) and a non-deviant group of nurses (n=79) randomly selected from a broader population. The hypothesis that the deviant group of nurses would exhibit lower PRB scores, on average, compared to the non-deviant group was confirmed. The mean PRB scores for the deviant nurses (m=32.43) were significantly lower (p.01) than for the randomly selected non-deviant nurses (m=35.06). A multiple regression logit analysis showed that in addition to PRB scores, college degree, sex, and household income variables were also significantly related (p.001) to deviant and non-deviant group assignment; nonetheless, PRB significantly differentiated these groups after holding these variables constant.This study is based on the Masters thesis research of the first author. We acknowledge the help of the study subjects who contributed their time and effort.  相似文献   
984.
This study further established the criterion-related validity of the Safety Locus of Control Scale. The safety scale was designed to predict employment applicants' propensity for on-the-job accidents. In this study, 283 hospital employees with moreexternal safety locus of control orientations reported significantly more occupational accidents, as well as more severe and costly injuries, than workers with moreinternal safety attitudes (p<.05 in all cases). Implications of these results are discussed.Research study presented at the 1988 Annual Conference of the Association of Human Resources Management and Organizational Behavior, Long Beach, California, October 26–29.  相似文献   
985.
This is an ecological test of adaptation in head-injured adults, reporting reliability and validity of the Executive Function Route-finding Task (EFRT; Boyd and Sautter, 1985). A Likert scale was used to rate executive aspects of route-finding such as task formulation, strategy of approach, detection and correction of errors, and dependence on cueing among 31 head-injured young adults within a large rehabilitation facility. The Task has high inter-rater reliability and acceptable concurrent validity with other neuropsychological constructs.  相似文献   
986.
Comparative analysis of 204 African-American and White students' perceptions toward secondary vocational education revealed that students formed perceptions toward these programs from a multidimensional perspective. Generally, African-American female students held positive perceptions whereas African-American male students held negative perceptions toward vocational education programs.  相似文献   
987.
988.
The central terms of certain theories which were valued highly in the past, such as the phlogiston theory, are now believed by realists not to refer. Laudan and others have claimed that, in the light of the existence of such theories, scientific realism is untenable. This paper argues in response that realism is consistent with — and indeed is able to explain — such theories' having been highly valued and yet not being close to the truth. It follows that the set of highly-valued past theories cited by Laudan, presumed to militate against realism, is in fact innocuous to the doctrine. The argument hinges largely on identifying the grounds on which theory-adoption is actually performed.  相似文献   
989.
The present study evaluated the efficacy of a new intervention, Guided Imaginal Coping (GIC), compared to imaginal exposure (IEX), and a waiting-list control (WLC) condition among 24 clinic outpatients meeting DSM-III-R criteria for panic disorder (PD) or PD with agoraphobia. GIC was the more consistently effective intervention, with individuals demonstrating significant improvement in frequency and severity of panic attacks (Pas) as well as significant reductions in physiological and subjective arousal to provocative imagery. Individuals in the IEX intervention demonstrated less consistent improvement on the dependent measures, while individuals in the WLC condition essentially remained unchanged. Both GIC and IEX were effective according to a composite measure of clinically significant improvement. However, only GIC was superior to the WLC condition when clinical improvement was defined as zero PAs at follow-up. These findings, while preliminary, suggest that GIC can be added to the armamentarium of effective approaches to treating PD.  相似文献   
990.
Research in a wide variety of domains provides converging evidence for the psychological unconscious—percepts, memories, and other mental contents that influence experience, thought, and action outside of phenomenal awareness. Studies of preconscious processing indicate that two continua underlie conscious experience—one having to do with the quality of the stimulus event or its mental representation, and the other having to do with the cognitive resources brought to hear on the processing of that representation. However, evidence of subconscious processing violates these conclusions and suggests that something more is involved—perhaps a link between mental representations of events and of the self as the agent or experiencer of them.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号